The research proposed in this application is designed to extend our knowledge of affect and cerebral asymmetry. The proposed set of experiments is based upon a growing body of literature which indicates that certain regions of the two cerebral hemispheres are asymmetrically activated during certain states of positive and negative emotion. The studies are designed to more specify the emotions for which asymmetries in activation are present, to explore the hemispheric substrates of certain affect/cognition interactions and to examine a group of depressed psychiatric patients to determine whether predicted dysfunctions in both affective and cognitive asymmetries are present. The first three studies will utilize two major methodological approaches in the study of emotion which have never, to date, been brought together in the same experiment. Measures of facial action from unobtrusively recorded video records will be obtaind to precisely specify the occurrence and type of discrete facial signs of emotion. At coincident points in time, quantitative measures of brain activity will be computer-extracted from the ongoing EEG. In this way, momentary changes in facial expression can be related to concurrent measures of asymmetric cortical activation. Another proposed experiment will examine the impact of phasic changes in emotional state on left and right hemisphere-mediated cognitive performance to explore the relations between asymmetries associated with affect and cognition. The final experiment will assess EEG asymmetries associated with affect and cognition in a group of depressed psychiatric patients and normal controls in order to further explore the hemispheric substrates of affect/cognition interactions in a clinical population which exhibits characteristic affective and cognitive dysfunctions.